LinuxLists.cc - [RFC PATCH 0/4] watchdog: at91sam9_wdt: handle already configured wdt

2013-06-11 10:51:50

Subject: [RFC PATCH 0/4] watchdog: at91sam9_wdt: handle already configured wdt

Hello,

This patch series is a porposal to enhance the sam9 watchdog timer support.

The at91sam9 watchdog timer cannot configured twice, and the current
implementation only tries to configure in a static way:
- 2 seconds timeout
- wdt restart every 500ms

If the timer has already been configured with different values, it returns an
error and do not create any watchdog device.

This is not critical if the watchdog is disabled, but if it has been enabled with
different timeout values it will lead to a SoC reset.

This patch series tries to address this issue by adapting the heartbeat value
according the WDT timer config:
- it first tries to configure the timer as requested.
- if it fails it fallbacks to the current config, adapting its heartbeat timer
to the needs

This patch series also move to a dynamically allocated at91wdt device instead
of the static instance. I'm not sure this is the best solution, so please tell
me if you prefer to keep static instance of watchdog.

It adds a new at91 wdt type: software. This new type make use of the at91 wdt
interrupt to trigger a software watchdog.

Finally it adds several properties to the device tree bindings.

Best Regards,
Boris

Boris BREZILLON (4):
watchdog: at91sam9_wdt: better watchdog support
watchdog: at91sam9_wdt: update device tree doc
ARM: at91/dt: add sam9 watchdog default options to SoCs
ARM: at91/dt: add watchdog properties to kizbox board

.../devicetree/bindings/watchdog/atmel-wdt.txt | 30 +-
arch/arm/boot/dts/at91sam9260.dtsi | 5 +
arch/arm/boot/dts/at91sam9263.dtsi | 5 +
arch/arm/boot/dts/at91sam9g45.dtsi | 5 +
arch/arm/boot/dts/at91sam9n12.dtsi | 5 +
arch/arm/boot/dts/at91sam9x5.dtsi | 5 +
arch/arm/boot/dts/kizbox.dts | 6 +
arch/arm/boot/dts/sama5d3.dtsi | 5 +
drivers/watchdog/at91sam9_wdt.c | 319 +++++++++++++++-----
9 files changed, 300 insertions(+), 85 deletions(-)

--
1.7.9.5

2013-06-11 10:51:54

by Boris BREZILLON

[permalink] [raw]

Subject: [RFC PATCH 1/4] watchdog: at91sam9_wdt: better watchdog support

The at91sam9 watchdog timer cannot configured twice, and the current
implementation only tries to configure in a static way:
- 2 seconds timeout
- wdt restart every 500ms

If the timer has already been configured with different values, it returns an
error and do not create any watchdog device.

This is not critical if the watchdog is disabled, but if it has been enabled with
different timeout values it will lead to a SoC reset.

This patch series tries to address this issue by adapting the heartbeat value
according the WDT timer config:
- it first tries to configure the timer as requested.
- if it fails it fallbacks to the current config, adapting its heartbeat timer
to the needs

This patch series also move to a dynamically allocated at91wdt device instead
of the static instance.

It adds a new at91 wdt type: software. This new type make use of the at91 wdt
interrupt to trigger a software watchdog.

Finally it adds several properties to the device tree bindings.

Signed-off-by: Boris BREZILLON <[email protected]>
---
drivers/watchdog/at91sam9_wdt.c | 319 +++++++++++++++++++++++++++++----------
1 file changed, 236 insertions(+), 83 deletions(-)

diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
index be37dde..fb47ec5 100644
--- a/drivers/watchdog/at91sam9_wdt.c
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -19,11 +19,13 @@

#include <linux/errno.h>
#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
#include <linux/types.h>
#include <linux/watchdog.h>
#include <linux/jiffies.h>
@@ -31,23 +33,32 @@
#include <linux/bitops.h>
#include <linux/uaccess.h>
#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>

#include "at91sam9_wdt.h"

#define DRV_NAME "AT91SAM9 Watchdog"

-#define wdt_read(field) \
- __raw_readl(at91wdt_private.base + field)
-#define wdt_write(field, val) \
- __raw_writel((val), at91wdt_private.base + field)
+#define wdt_read(wdt, field) \
+ __raw_readl((wdt)->base + field)
+#define wdt_write(wtd, field, val) \
+ __raw_writel((val), (wdt)->base + field)

/* AT91SAM9 watchdog runs a 12bit counter @ 256Hz,
* use this to convert a watchdog
* value from/to milliseconds.
*/
+#define hz_to_ticks(h) (((h << 8) / HZ) - 1)
+#define ticks_to_hz(t) (((t + 1) * HZ) >> 8)
#define ms_to_ticks(t) (((t << 8) / 1000) - 1)
#define ticks_to_ms(t) (((t + 1) * 1000) >> 8)

+#define WDT_MR_RESET 0x3FFF2FFF
+
+#define WDT_WDD_MAX 0xFFF
+#define WDT_WDV_MAX 0xFFF
+
/* Hardware timeout in seconds */
#define WDT_HW_TIMEOUT 2

@@ -66,23 +77,41 @@ module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

-static struct watchdog_device at91_wdt_dev;
-static void at91_ping(unsigned long data);
-
-static struct {
+#define to_wdt(wdd) container_of(wdd, struct at91wdt, wdd)
+struct at91wdt {
+ struct watchdog_device wdd;
void __iomem *base;
unsigned long next_heartbeat; /* the next_heartbeat for the timer */
struct timer_list timer; /* The timer that pings the watchdog */
-} at91wdt_private;
+ u32 mr;
+ u32 mr_mask;
+ unsigned long heartbeat; /* WDT heartbeat in jiffies */
+ bool nowayout;
+ unsigned int irq;
+};

/* ......................................................................... */

+static irqreturn_t wdt_interrupt(int irq, void *dev_id)
+{
+ struct at91wdt *wdt = (struct at91wdt *)dev_id;
+
+ if (wdt_read(wdt, AT91_WDT_SR)) {
+ /* Reboot */
+ pr_crit("at91sam9 WDT software reset\n");
+ emergency_restart();
+ pr_crit("Reboot didn't ?????\n");
+ }
+
+ return IRQ_HANDLED;
+}
+
/*
* Reload the watchdog timer. (ie, pat the watchdog)
*/
-static inline void at91_wdt_reset(void)
+static inline void at91_wdt_reset(struct at91wdt *wdt)
{
- wdt_write(AT91_WDT_CR, AT91_WDT_KEY | AT91_WDT_WDRSTT);
+ wdt_write(wdt, AT91_WDT_CR, AT91_WDT_KEY | AT91_WDT_WDRSTT);
}

/*
@@ -90,26 +119,20 @@ static inline void at91_wdt_reset(void)
*/
static void at91_ping(unsigned long data)
{
- if (time_before(jiffies, at91wdt_private.next_heartbeat) ||
- (!watchdog_active(&at91_wdt_dev))) {
- at91_wdt_reset();
- mod_timer(&at91wdt_private.timer, jiffies + WDT_TIMEOUT);
+ struct at91wdt *wdt = (struct at91wdt *)data;
+ if (time_before(jiffies, wdt->next_heartbeat) ||
+ (!watchdog_active(&wdt->wdd))) {
+ at91_wdt_reset(wdt);
+ mod_timer(&wdt->timer, jiffies + wdt->heartbeat);
} else
pr_crit("I will reset your machine !\n");
}

static int at91_wdt_ping(struct watchdog_device *wdd)
{
+ struct at91wdt *wdt = to_wdt(wdd);
/* calculate when the next userspace timeout will be */
- at91wdt_private.next_heartbeat = jiffies + wdd->timeout * HZ;
- return 0;
-}
-
-static int at91_wdt_start(struct watchdog_device *wdd)
-{
- /* calculate the next userspace timeout and modify the timer */
- at91_wdt_ping(wdd);
- mod_timer(&at91wdt_private.timer, jiffies + WDT_TIMEOUT);
+ wdt->next_heartbeat = jiffies + wdd->timeout * HZ;
return 0;
}

@@ -125,36 +148,82 @@ static int at91_wdt_set_timeout(struct watchdog_device *wdd, unsigned int new_ti
return 0;
}

-/*
- * Set the watchdog time interval in 1/256Hz (write-once)
- * Counter is 12 bit.
- */
-static int at91_wdt_settimeout(unsigned int timeout)
+static int at91_wdt_init(struct platform_device *pdev, struct at91wdt *wdt)
{
- unsigned int reg;
- unsigned int mr;
-
- /* Check if disabled */
- mr = wdt_read(AT91_WDT_MR);
- if (mr & AT91_WDT_WDDIS) {
- pr_err("sorry, watchdog is disabled\n");
- return -EIO;
+ u32 tmp;
+ u32 delta;
+ u32 value;
+ int err;
+ u32 mask = wdt->mr_mask;
+
+ tmp = wdt_read(wdt, AT91_WDT_MR);
+ if ((tmp & mask) != (wdt->mr & mask)) {
+ if (tmp == WDT_MR_RESET) {
+ wdt_write(wdt, AT91_WDT_MR, wdt->mr);
+ tmp = wdt_read(wdt, AT91_WDT_MR);
+ }
+ }
+
+ if (tmp & AT91_WDT_WDDIS) {
+ if (wdt->mr & AT91_WDT_WDDIS)
+ return 0;
+ dev_err(wdt->wdd.parent,
+ ": sorry, watchdog is disabled\n");
+ return -EINVAL;
+ }
+
+ value = tmp & AT91_WDT_WDV;
+ delta = (tmp & AT91_WDT_WDD) >> 16;
+
+ if (delta < value) {
+ if ((value / (value - delta)) < 4) {
+ dev_err(wdt->wdd.parent,
+ ": sorry, max-heartbeat should be at least 4 times min-heartbeat (max-heartbeat = %d x min-heartbeat)\n",
+ (value / (value - delta)));
+ return -EINVAL;
+ }
+ }
+
+ wdt->heartbeat = ticks_to_hz(value / 4);
+
+ if (!wdt->heartbeat) {
+ dev_err(wdt->wdd.parent,
+ ": sorry, linux timer (%i Hz) cannot handle watchdog timeout (%i ms)\n",
+ HZ, ticks_to_ms(value));
+ return -EINVAL;
+ }
+
+ if ((tmp & AT91_WDT_WDFIEN) && wdt->irq) {
+ err = request_irq(wdt->irq, wdt_interrupt,
+ IRQF_SHARED | IRQF_IRQPOLL,
+ pdev->name, wdt);
+ if (err)
+ return err;
}

- /*
- * All counting occurs at SLOW_CLOCK / 128 = 256 Hz
- *
- * Since WDV is a 12-bit counter, the maximum period is
- * 4096 / 256 = 16 seconds.
- */
- reg = AT91_WDT_WDRSTEN /* causes watchdog reset */
- /* | AT91_WDT_WDRPROC causes processor reset only */
- | AT91_WDT_WDDBGHLT /* disabled in debug mode */
- | AT91_WDT_WDD /* restart at any time */
- | (timeout & AT91_WDT_WDV); /* timer value */
- wdt_write(AT91_WDT_MR, reg);
+ if ((tmp & wdt->mr_mask) != (wdt->mr & wdt->mr_mask))
+ dev_warn(wdt->wdd.parent,
+ ": watchdog already configured differently (mr = %x expecting %x)\n",
+ tmp & wdt->mr_mask, wdt->mr & wdt->mr_mask);
+
+ setup_timer(&wdt->timer, at91_ping, (unsigned long)wdt);
+ mod_timer(&wdt->timer, jiffies + wdt->heartbeat);
+
+ /* Try to set timeout from device tree first */
+ if (watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev))
+ watchdog_init_timeout(&wdt->wdd, heartbeat, &pdev->dev);
+ watchdog_set_nowayout(&wdt->wdd, wdt->nowayout);
+ err = watchdog_register_device(&wdt->wdd);
+ if (err)
+ goto out_stop_timer;
+
+ wdt->next_heartbeat = jiffies + wdt->wdd.timeout * HZ;

return 0;
+
+out_stop_timer:
+ del_timer(&wdt->timer);
+ return err;
}

/* ......................................................................... */
@@ -167,63 +236,147 @@ static const struct watchdog_info at91_wdt_info = {

static const struct watchdog_ops at91_wdt_ops = {
.owner = THIS_MODULE,
- .start = at91_wdt_start,
+ .start = at91_wdt_ping,
.stop = at91_wdt_stop,
.ping = at91_wdt_ping,
.set_timeout = at91_wdt_set_timeout,
};

-static struct watchdog_device at91_wdt_dev = {
- .info = &at91_wdt_info,
- .ops = &at91_wdt_ops,
- .timeout = WDT_HEARTBEAT,
- .min_timeout = 1,
- .max_timeout = 0xFFFF,
-};
+#if defined(CONFIG_OF)
+static int of_at91wdt_init(struct device_node *np, struct at91wdt *wdt)
+{
+ u32 min = 0;
+ u32 max = 0xFFF;
+ const char *tmp;
+
+ wdt->base = of_iomap(np, 0);
+ if (!wdt->base) {
+ dev_err(wdt->wdd.parent, "failed to map registers, aborting.\n");
+ return -EINVAL;
+ }
+
+ /* Get the interrupts property */
+ wdt->irq = irq_of_parse_and_map(np, 0);
+ if (!wdt->irq)
+ dev_warn(wdt->wdd.parent, "failed to get IRQ from DT.\n");
+
+ if (!of_property_read_u32_index(np, "atmel,max-heartbeat-sec", 0,
+ &max)) {
+ max *= 256;
+ if (max > WDT_WDV_MAX)
+ max = WDT_WDV_MAX;
+
+ if (!of_property_read_u32_index(np, "atmel,min-heartbeat-sec",
+ 0, &min)) {
+ min *= 256;
+ if (4 * min > max)
+ min = max / 4;
+ }
+ }
+
+ wdt->mr_mask = 0x3FFFFFFF;
+ wdt->mr = 0;
+ if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
+ !strcmp(tmp, "software")) {
+ wdt->mr |= AT91_WDT_WDFIEN;
+ wdt->mr_mask &= ~AT91_WDT_WDRPROC;
+ } else
+ wdt->mr |= AT91_WDT_WDRSTEN;
+
+ if (!of_property_read_string(np, "atmel,reset-type", &tmp) &&
+ !strcmp(tmp, "proc"))
+ wdt->mr |= AT91_WDT_WDRPROC;
+
+ if (of_property_read_bool(np, "atmel,disable")) {
+ wdt->mr |= AT91_WDT_WDDIS;
+ wdt->mr_mask &= AT91_WDT_WDDIS;
+ }
+
+ if (of_property_read_bool(np, "atmel,idle-halt"))
+ wdt->mr |= AT91_WDT_WDIDLEHLT;
+
+ if (of_property_read_bool(np, "atmel,dbg-halt"))
+ wdt->mr |= AT91_WDT_WDDBGHLT;
+
+ wdt->mr |= max | ((max - min) << 16);
+
+ return 0;
+}
+#else
+static inline int of_at91wdt_init(struct device_node *np, struct at91wdt *wdt)
+{
+ return 0;
+}
+#endif

static int __init at91wdt_probe(struct platform_device *pdev)
{
struct resource *r;
- int res;
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!r)
- return -ENODEV;
- at91wdt_private.base = ioremap(r->start, resource_size(r));
- if (!at91wdt_private.base) {
- dev_err(&pdev->dev, "failed to map registers, aborting.\n");
- return -ENOMEM;
- }
+ int err;
+ struct at91wdt *wdt;

- at91_wdt_dev.parent = &pdev->dev;
- watchdog_init_timeout(&at91_wdt_dev, heartbeat, &pdev->dev);
- watchdog_set_nowayout(&at91_wdt_dev, nowayout);
+ wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+ if (!wdt)
+ return -ENOMEM;

- /* Set watchdog */
- res = at91_wdt_settimeout(ms_to_ticks(WDT_HW_TIMEOUT * 1000));
- if (res)
- return res;
+ wdt->mr = (WDT_HW_TIMEOUT * 256) | AT91_WDT_WDRSTEN | AT91_WDT_WDD |
+ AT91_WDT_WDDBGHLT | AT91_WDT_WDIDLEHLT;
+ wdt->mr_mask = 0x3FFFFFFF;
+ wdt->nowayout = nowayout;
+ wdt->wdd.parent = &pdev->dev;
+ wdt->wdd.info = &at91_wdt_info;
+ wdt->wdd.ops = &at91_wdt_ops;
+ wdt->wdd.timeout = WDT_HEARTBEAT;
+ wdt->wdd.min_timeout = 1;
+ wdt->wdd.max_timeout = 0xFFFF;
+
+ if (pdev->dev.of_node) {
+ err = of_at91wdt_init(pdev->dev.of_node, wdt);
+ if (err)
+ goto out_free_watchdog;
+ } else {
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ err = -ENODEV;
+ goto out_free_watchdog;
+ }
+
+ wdt->base = ioremap(r->start, resource_size(r));
+ if (!wdt->base) {
+ dev_err(&pdev->dev, "failed to map registers, aborting.\n");
+ err = -ENOMEM;
+ goto out_free_watchdog;
+ }
+ }

- res = watchdog_register_device(&at91_wdt_dev);
- if (res)
- return res;
+ err = at91_wdt_init(pdev, wdt);
+ if (err)
+ goto out_iounmap;

- at91wdt_private.next_heartbeat = jiffies + at91_wdt_dev.timeout * HZ;
- setup_timer(&at91wdt_private.timer, at91_ping, 0);
- mod_timer(&at91wdt_private.timer, jiffies + WDT_TIMEOUT);
+ platform_set_drvdata(pdev, wdt);

pr_info("enabled (heartbeat=%d sec, nowayout=%d)\n",
- at91_wdt_dev.timeout, nowayout);
+ wdt->wdd.timeout, wdt->nowayout);

return 0;
+
+out_iounmap:
+ iounmap(wdt->base);
+out_free_watchdog:
+ devm_kfree(&pdev->dev, wdt);
+ return err;
}

static int __exit at91wdt_remove(struct platform_device *pdev)
{
- watchdog_unregister_device(&at91_wdt_dev);
+ struct at91wdt *wdt = platform_get_drvdata(pdev);
+ watchdog_unregister_device(&wdt->wdd);

pr_warn("I quit now, hardware will probably reboot!\n");
- del_timer(&at91wdt_private.timer);
+ del_timer(&wdt->timer);
+
+ iounmap(wdt->base);
+ devm_kfree(&pdev->dev, wdt);

return 0;
}
--
1.7.9.5

2013-06-11 10:52:32

by Boris BREZILLON

[permalink] [raw]

Subject: [RFC PATCH 3/4] ARM: at91/dt: add sam9 watchdog default options to SoCs

Set default watchdog options in every SoC compatible with the sam9 watchdog.

Signed-off-by: Boris BREZILLON <[email protected]>
---
arch/arm/boot/dts/at91sam9260.dtsi | 5 +++++
arch/arm/boot/dts/at91sam9263.dtsi | 5 +++++
arch/arm/boot/dts/at91sam9g45.dtsi | 5 +++++
arch/arm/boot/dts/at91sam9n12.dtsi | 5 +++++
arch/arm/boot/dts/at91sam9x5.dtsi | 5 +++++
arch/arm/boot/dts/sama5d3.dtsi | 5 +++++
6 files changed, 30 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9260.dtsi b/arch/arm/boot/dts/at91sam9260.dtsi
index 899a7cf..6c44c35 100644
--- a/arch/arm/boot/dts/at91sam9260.dtsi
+++ b/arch/arm/boot/dts/at91sam9260.dtsi
@@ -643,6 +643,11 @@
watchdog@fffffd40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffd40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};
};
diff --git a/arch/arm/boot/dts/at91sam9263.dtsi b/arch/arm/boot/dts/at91sam9263.dtsi
index ff63811..6b31ee0 100644
--- a/arch/arm/boot/dts/at91sam9263.dtsi
+++ b/arch/arm/boot/dts/at91sam9263.dtsi
@@ -519,6 +519,11 @@
watchdog@fffffd40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffd40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index faec17d..ca1a643 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -634,6 +634,11 @@
watchdog@fffffd40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffd40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};

diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index 3166e1d..7c8a5ea 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -505,6 +505,11 @@
watchdog@fffffe40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffe40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};
};
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index e77106e..48eb1cc 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -742,6 +742,11 @@
watchdog@fffffe40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffe40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};

diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
index c00e158..7974723 100644
--- a/arch/arm/boot/dts/sama5d3.dtsi
+++ b/arch/arm/boot/dts/sama5d3.dtsi
@@ -885,6 +885,11 @@
watchdog@fffffe40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffe40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
status = "disabled";
};

--
1.7.9.5

2013-06-11 10:52:31

by Boris BREZILLON

[permalink] [raw]

Subject: [RFC PATCH 4/4] ARM: at91/dt: add watchdog properties to kizbox board

Add watchdog specific config for kizbox board.

Signed-off-by: Boris BREZILLON <[email protected]>
---
arch/arm/boot/dts/kizbox.dts | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/arm/boot/dts/kizbox.dts b/arch/arm/boot/dts/kizbox.dts
index 02df191..928f6ee 100644
--- a/arch/arm/boot/dts/kizbox.dts
+++ b/arch/arm/boot/dts/kizbox.dts
@@ -53,6 +53,12 @@
status = "okay";
};

+ watchdog@fffffd40 {
+ timeout-sec = <15>;
+ atmel,max-heartbeat-sec = <16>;
+ atmel,min-heartbeat-sec = <0>;
+ status = "okay";
+ };
};

nand0: nand@40000000 {
--
1.7.9.5

2013-06-11 11:00:30

by Boris BREZILLON

[permalink] [raw]

Subject: [RFC PATCH 2/4] watchdog: at91sam9_wdt: update device tree doc

Add new at91sam9 watchdog properties to the documentation.

Signed-off-by: Boris BREZILLON <[email protected]>
---
.../devicetree/bindings/watchdog/atmel-wdt.txt | 30 ++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
index fcdd48f..e043106 100644
--- a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
@@ -9,11 +9,37 @@ Required properties:

Optional properties:
- timeout-sec: contains the watchdog timeout in seconds.
+- interrupts : Should contain WDT interrupt.
+- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in
+ seconds. This value should be less than 16. It is used to compute the
+ WDV field.
+- atmel,max-heartbeat-sec : Should contain the minimum heartbeat value in
+ seconds. This value should be less than 4 times the max-heartbeat-sec
+ value. It is used to compute the WDD field.
+- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog
+ use the at91 watchdog reset. Software watchdog use the watcdog interrup
+ to trigger a software reset.
+- atmel,reset-type : Should be "proc" or "all".
+ "all" : assert peripherals and processor reset signals
+ "proc" : assert the processor reset signal
+ This is valid only when using "hardware" watchdog.
+- atmel,disable : Should be present if you want to disable the watchdog.
+- atmel,idle-halt : Should be present if you want to stop the watchdog when
+ entering idle state.
+- atmel,dbg-halt : Should be present if you want to stop the watchdog when
+ entering debug state.

Example:
-
watchdog@fffffd40 {
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffd40 0x10>;
- timeout-sec = <10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ timeout-sec = <15>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
+ atmel,max-heartbeat-sec = <16>;
+ atmel,min-heartbeat-sec = <0>;
+ status = "okay";
};
--
1.7.9.5

2013-06-11 22:29:43

by Grant Likely

[permalink] [raw]

Subject: Re: [RFC PATCH 2/4] watchdog: at91sam9_wdt: update device tree doc

On Tue, 11 Jun 2013 12:51:27 +0200, Boris BREZILLON <[email protected]> wrote:
> Add new at91sam9 watchdog properties to the documentation.
>
> Signed-off-by: Boris BREZILLON <[email protected]>

Looks reasonable,

Acked-by: Grant Likely <[email protected]>

> ---
> .../devicetree/bindings/watchdog/atmel-wdt.txt | 30 ++++++++++++++++++--
> 1 file changed, 28 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> index fcdd48f..e043106 100644
> --- a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> +++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> @@ -9,11 +9,37 @@ Required properties:
>
> Optional properties:
> - timeout-sec: contains the watchdog timeout in seconds.
> +- interrupts : Should contain WDT interrupt.
> +- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in
> + seconds. This value should be less than 16. It is used to compute the
> + WDV field.
> +- atmel,max-heartbeat-sec : Should contain the minimum heartbeat value in
> + seconds. This value should be less than 4 times the max-heartbeat-sec
> + value. It is used to compute the WDD field.
> +- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog
> + use the at91 watchdog reset. Software watchdog use the watcdog interrup
> + to trigger a software reset.
> +- atmel,reset-type : Should be "proc" or "all".
> + "all" : assert peripherals and processor reset signals
> + "proc" : assert the processor reset signal
> + This is valid only when using "hardware" watchdog.
> +- atmel,disable : Should be present if you want to disable the watchdog.
> +- atmel,idle-halt : Should be present if you want to stop the watchdog when
> + entering idle state.
> +- atmel,dbg-halt : Should be present if you want to stop the watchdog when
> + entering debug state.
>
> Example:
> -
> watchdog@fffffd40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffd40 0x10>;
> - timeout-sec = <10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + timeout-sec = <15>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> + atmel,max-heartbeat-sec = <16>;
> + atmel,min-heartbeat-sec = <0>;
> + status = "okay";
> };
> --
> 1.7.9.5
>

--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.

2013-06-21 01:42:42

by Wenyou Yang

[permalink] [raw]

Subject: RE: [RFC PATCH 2/4] watchdog: at91sam9_wdt: update device tree doc

2013-06-21 01:45:54

by Wenyou Yang

[permalink] [raw]

Subject: RE: [RFC PATCH 3/4] ARM: at91/dt: add sam9 watchdog default options to SoCs

> -----Original Message-----
> From: linux-arm-kernel [mailto:[email protected]]
> On Behalf Of Boris BREZILLON
> Sent: 2013??6??11?? 18:51
> To: Wim Van Sebroeck; Jean-Christophe Plagniol-Villard; Ferre, Nicolas
> Cc: Boris BREZILLON; Russell King; [email protected];
> [email protected]; [email protected]
> Subject: [RFC PATCH 3/4] ARM: at91/dt: add sam9 watchdog default options to
> SoCs
>
> Set default watchdog options in every SoC compatible with the sam9 watchdog.
>
> Signed-off-by: Boris BREZILLON <[email protected]>
> ---
> arch/arm/boot/dts/at91sam9260.dtsi | 5 +++++
> arch/arm/boot/dts/at91sam9263.dtsi | 5 +++++
> arch/arm/boot/dts/at91sam9g45.dtsi | 5 +++++
> arch/arm/boot/dts/at91sam9n12.dtsi | 5 +++++
> arch/arm/boot/dts/at91sam9x5.dtsi | 5 +++++
> arch/arm/boot/dts/sama5d3.dtsi | 5 +++++
> 6 files changed, 30 insertions(+)
>
> diff --git a/arch/arm/boot/dts/at91sam9260.dtsi
> b/arch/arm/boot/dts/at91sam9260.dtsi
> index 899a7cf..6c44c35 100644
> --- a/arch/arm/boot/dts/at91sam9260.dtsi
> +++ b/arch/arm/boot/dts/at91sam9260.dtsi
> @@ -643,6 +643,11 @@
> watchdog@fffffd40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffd40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
> };
> diff --git a/arch/arm/boot/dts/at91sam9263.dtsi
> b/arch/arm/boot/dts/at91sam9263.dtsi
> index ff63811..6b31ee0 100644
> --- a/arch/arm/boot/dts/at91sam9263.dtsi
> +++ b/arch/arm/boot/dts/at91sam9263.dtsi
> @@ -519,6 +519,11 @@
> watchdog@fffffd40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffd40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
>
> diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi
> b/arch/arm/boot/dts/at91sam9g45.dtsi
> index faec17d..ca1a643 100644
> --- a/arch/arm/boot/dts/at91sam9g45.dtsi
> +++ b/arch/arm/boot/dts/at91sam9g45.dtsi
> @@ -634,6 +634,11 @@
> watchdog@fffffd40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffd40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
>
> diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi
> b/arch/arm/boot/dts/at91sam9n12.dtsi
> index 3166e1d..7c8a5ea 100644
> --- a/arch/arm/boot/dts/at91sam9n12.dtsi
> +++ b/arch/arm/boot/dts/at91sam9n12.dtsi
> @@ -505,6 +505,11 @@
> watchdog@fffffe40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffe40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
> };
> diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi
> b/arch/arm/boot/dts/at91sam9x5.dtsi
> index e77106e..48eb1cc 100644
> --- a/arch/arm/boot/dts/at91sam9x5.dtsi
> +++ b/arch/arm/boot/dts/at91sam9x5.dtsi
> @@ -742,6 +742,11 @@
> watchdog@fffffe40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffe40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
>
> diff --git a/arch/arm/boot/dts/sama5d3.dtsi
> b/arch/arm/boot/dts/sama5d3.dtsi
> index c00e158..7974723 100644
> --- a/arch/arm/boot/dts/sama5d3.dtsi
> +++ b/arch/arm/boot/dts/sama5d3.dtsi
> @@ -885,6 +885,11 @@
> watchdog@fffffe40 {
> compatible = "atmel,at91sam9260-wdt";
> reg = <0xfffffe40 0x10>;
> + interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
Change it with,
interrupts = <4 IRQ_TYPE_LEVEL_HIGH 7>;
Because in sama5d3, watchdog interrupt is not shared with SYSC, it uses a separate interrupt line, 4.
> + atmel,watchdog-type = "hardware";
> + atmel,reset-type = "all";
> + atmel,dbg-halt;
> + atmel,idle-halt;
> status = "disabled";
> };
>
> --
> 1.7.9.5
>
>
Best Regards,
Wenyou Yang
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m????????????I?

2013-06-21 01:48:47

by Wenyou Yang

[permalink] [raw]

Subject: RE: [RFC PATCH 0/4] watchdog: at91sam9_wdt: handle already configured wdt

2013-06-21 06:59:47

by Boris BREZILLON

[permalink] [raw]

Subject: Re: [RFC PATCH 0/4] watchdog: at91sam9_wdt: handle already configured wdt

On 21/06/2013 03:47, Yang, Wenyou wrote:
>
>> -----Original Message-----
>> From: linux-arm-kernel [mailto:[email protected]]
>> On Behalf Of Boris BREZILLON
>> Sent: 2013??6??11?? 18:51
>> To: Wim Van Sebroeck; Jean-Christophe Plagniol-Villard; Ferre, Nicolas;
>> [email protected]
>> Cc: [email protected]; [email protected];
>> [email protected]; [email protected]; Boris
>> BREZILLON
>> Subject: [RFC PATCH 0/4] watchdog: at91sam9_wdt: handle already configured
>> wdt
>>
>> Hello,
>>
>> This patch series is a porposal to enhance the sam9 watchdog timer support.
>>
>> The at91sam9 watchdog timer cannot configured twice, and the current
>> implementation only tries to configure in a static way:
>> - 2 seconds timeout
>> - wdt restart every 500ms
>>
>> If the timer has already been configured with different values, it returns an
>> error and do not create any watchdog device.
>>
>> This is not critical if the watchdog is disabled, but if it has been enabled with
>> different timeout values it will lead to a SoC reset.
>>
>> This patch series tries to address this issue by adapting the heartbeat value
>> according the WDT timer config:
>> - it first tries to configure the timer as requested.
>> - if it fails it fallbacks to the current config, adapting its heartbeat timer
>> to the needs
>>
>> This patch series also move to a dynamically allocated at91wdt device instead
>> of the static instance. I'm not sure this is the best solution, so please tell
>> me if you prefer to keep static instance of watchdog.
>>
>> It adds a new at91 wdt type: software. This new type make use of the at91 wdt
>> interrupt to trigger a software watchdog.
>>
>> Finally it adds several properties to the device tree bindings.
>>
>> Best Regards,
>> Boris
>>
>> Boris BREZILLON (4):
>> watchdog: at91sam9_wdt: better watchdog support
>> watchdog: at91sam9_wdt: update device tree doc
>> ARM: at91/dt: add sam9 watchdog default options to SoCs
>> ARM: at91/dt: add watchdog properties to kizbox board
>>
>> .../devicetree/bindings/watchdog/atmel-wdt.txt | 30 +-
>> arch/arm/boot/dts/at91sam9260.dtsi | 5 +
>> arch/arm/boot/dts/at91sam9263.dtsi | 5 +
>> arch/arm/boot/dts/at91sam9g45.dtsi | 5 +
>> arch/arm/boot/dts/at91sam9n12.dtsi | 5 +
>> arch/arm/boot/dts/at91sam9x5.dtsi | 5 +
>> arch/arm/boot/dts/kizbox.dts | 6 +
>> arch/arm/boot/dts/sama5d3.dtsi | 5 +
>> drivers/watchdog/at91sam9_wdt.c | 319
>> +++++++++++++++-----
>> 9 files changed, 300 insertions(+), 85 deletions(-)
>>
>> --
>> 1.7.9.5
>>
>>
> Tested on sama5d34ek, at91sam9g25ek, linux-next_20130620
>
> Tested by Wenyou Yang <[email protected]>
>
Thanks for your tests and review.

Best Regards,

Boris
>> _______________________________________________
>> linux-arm-kernel mailing list
>> [email protected]
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel